A radical transformation of the Basilica is recorded in the second quarter of the 11th century CE
following a fire, of which extensive traces have been found. In addition to conspicuous transformations of
a structural nature, the floor of all the sections of the Basilica was raised by about 1 m. In the church,
starting from this date until its destruction, numerous burials were built including several masonry
ossuaries. New changes to the structure of the church were made during the second half of the fifteenth
century. The numismatic artifacts found have allowed us to date, at the beginning of the last quarter of the
fifteenth century, a large mass grave in which hundreds of burials were deposited (SU17, SU30 and
SU471). In the way of organizing the burials it is likely to recognize the effects of a plague epidemic
which we know to have struck the city between 1476 and 1479 CE, a hypothesis that would also be
confirmed by the study of skeletal remains. In 1489 CE the building of the Palazzo della Cancelleria
begins and the church is totally destroyed.
The population of this necropolis covers most of the Middle
Ages and is representative of the population of Rome of this period.